levin



May 15, 1956 A. I EvlN AUXILIARY AIR FEEDING DEVICE FOR sTovEs Filed Sept. 29, 1952 Hll- IN VENTOR @Lm ATTORNEY Alexander Levin, Washington, "assigner to the United States of America as represented by the Secretary of the Army Y Application september 29, 1952, senat No. 312,180 L p 4 Claims. (Ci. 12e-77) (Granted under Tine 35, U. s. Code (i952), sec. 266) The invention described herein, if patented, may be manufactured andused by or fory the Goverment for governmental purposes, withoutV the paymentto me of any royalty thereon.,

` My invention relates to an auxiliary air feeding devic for stoves.

An important object of the invention is to provide a device in the form of an attachment unit for a coal burning stove, such as a tent stove, in order to introduce additional air into the combustion space in order. to more completely burn the volatile combustion products.

A further object is to provide an auxiliary air feeding unit of the above-mentioned character which may be applied to an existing standard type stove without altering the construction of the same.

' A further object is to provide a device of the abovementioned character which is highly simplified and compact in construction and easy to apply to and remove from the stove.

A further important object is to provide a device of the above-mentioned character which will materially reduce smoking ofstoves which burn a low grade of bituminous coal, by supplying-additional air into the hightemperature zone to promote as nearly complete combustion as possible.

Still another object of the invention is to provide a unit of the above-mentioned character which is inexpensive and lightweight. I

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawings, forming a part of this application, and in which like numerals are employed to designate like parts throughout the same,

Figure l is a perspective View of a coal burning stove for tents or the like equipped with theauxiliary air, feeding unit embodying the invention,

Figure 2 is an enlarged central vertical section through the stove and unit,

Figure 3 is a horizontal cross section on line 3 3 of Figure 2,

Figure 4 is a similar section on line and,

Figure 5 is a similar section on line 5 5 of Figure 2.

In the drawings, where for the purpose of illustration is shown a preferred embodiment of the invention, the numeral designates generally a coal burning stove comprising upper and lower separable sections 11 and 12. The lower section 12 of the stove is provided with a suitable grate 13, and has a door 14 providing access to 4 4 of Figure 2,

an ash pit 15 within the lower section 12 below the grate. f

the adapter or connecting part for a chimney or smoke- 2,745,391 Patented ,May 15, 1956 'ice ' stack 20 when the stove is used without the unit embodylAUXILIARY AIR FEEDNG DEVICE FOR STOVES y 5 ing my invention. u My unit 21 comprises a spider-like support including a plurality of short radial lugs or pins 22 which are horizontally disposed and adapted to'restl upon the AtopL of the collar 19, Figure 2. The pins 22 are preferably four inl number, althoughfsix or more of the pinsl may be employed if desired. The vpins 22 have their inner endsy extending through radial openings 'formed in an adapten sleeve 23, vvand permanently rigidly secured thereto welding. or the like. The inner ends ofthe pin 22 project radially inwardly of the side wall ofthe adapter sleeve 23 as shown in Figure2 for a purpose to be described. Tli'e outer ends of the pins 22 are preferably rigidly secured to an annular band or centering ring'22'y which fits .on the opstanding sleeve19, as shown.

The adapter sleeve 23 includes an upper. enlarged sleeve extension 24, integral therewith and being of the same diameter as the collar 19 and adapted to serve like the collar 19 as the connecting part for the chimney 20 which has its lower end telescopically engaging over the sleeve extension 24, as shown. Y

The. unit 21 further comprises an innerdownwardly daring conical duct section or nozzle 25, provided at its upper end with a reduced cylindrical neck 26, integral therewith and provided in its top end with a plurality of L-shaped slots 27, corresponding in number vand spacing to the radial pins 22. The cylindrical neck 26 extends through the stove collar 19 and is substantially smaller in diameter than the stove collar so as to provide Y a substantial annular passage 27 to permitthe downward ow of air into the stove. Theneck 26 projectsslightly above the upper end 4of the collar 19 and is adaptedwto lit slidably within the adapter sleeve 23as shown; When the neck 26 is introduced into the adapter -sleeve 23, the

upper ends of the L-shaped slots 27 are aligned with the the,Y horizontal portions of the Vslots `27' as shownpand releasably lock the nozzle 25 within theY adapter sleeve. 23 and collar 19. The entirenozzle 25 is now suspended from the top of the collar-19h31 jmeans of the spider-like support includingthe pins 22 `and adapter sleeve 2 3. As shown in Figure 2, the lower ared end of the nozzle 25 is open and spaced nearl and above the lower end of fthe upper stove section 11. The nozzle 25 is preferably provided near its lowerend with a plurality lof circumferentially spaced air inlet operiings28. v

The unit 21 further comprises an outer conical wall or hood 29, `separate from the inner nozzle 25 and having the same degree of taper as the inner nozzle but being substantially larger in diameter, as shown. The lower open end 30 of the outer hood 29 is spaced'somewhat above the lower end. of the inner nozzle 25,` and preferably terminates at the group of openings 28. The hood 29 is supported by a plurality of substantially radial lugs 31, rigidly secured to the inner nozzle 25 at suitably spaced points, and the upper end of the conical'hood 29 contacts the lower end of the stovepipe collar `19 and has the same diameter as this collar so as to provide a continuous downwardly flaring annular passage 32, communicating with the annular passage 27. and leading at the lower end of the hood 29into the main combustion space of the stove. The hood 29. is not attached to the collar 19 directlybut merely bears against the lower end of the same. Neitheris the hood 2 permanently secured .to the inner nozzle 25, but merely suspended thereon by adapter sleeve 23 and lowered, both the inner nozzle 25 rate of combustion. A Y In; order to prevent'the accumulation of any substantial guantity'oi volatile mixture nearfthe top of the stove,

I may form'one or-more of the uppermost lugs 31 tubu- ,Y

and outerV hood 29`are readily the unit21` from the stove, the outer. hood 29 isA readily after removal downwardly ofthe unit 21. f

removable downwardly from the upper stove section 11, and Vafter removal ofV removable upwardly Vfrom the inner nozzlev vThe spiderltype'support includi'ngthe adapter sleeve 2 3 and radial pins 22 may be readily lifted from the collar '19;

As previously mentioned, the purpose of the unitV 2 1is' to introduce secondary air intothe high temperature TVzone where its ow can be brought into intimate *contact with the coal volatiles for ignition. The arrangement isv designed so that a substantial supply of air can'be drawn into thestove through the-passageSZ and'oriticeszS to provide auxiliary air where' itis foundlthat air infiltration through the lid l18V is insufficient to'supportthe required laryasV at 33, for registration with small openings 3 3' in the hood 29, near the upper end of the same.` This places the interior Vofthe nozzle 25 in communication with the mainrcombustion space near the top of upperV stove sec-` tion 11. Withthis arrangement, the volatiles which teud i to accumulateV at the top of the stove will bedrawn into, the nozzle 25 and ignited by the hot combustion products rising through vthe nozzle 25,y If desired, the openings33 and the openings of theuppermost lugs 31 may be omitted' entirelyiV I In use,'as the bituminous coal on the grate 13 burns, some air enters the stove through the top lid 18 for supporting combustion. The hot combustionY products will rise through the tapered innernozzlel25 and enter the chimney 21, thusl creatinga strongup-draft and suction. Whenthis occurs, fresh air will be drawn into the top ofthe-collar 19, exteriorly ofz the lneck 26 and down- 22.. This downwardly flowing auxiliaryair will enter the 4' main Acombustion space ofthe Vstove from the lower end of the passage32,'and some ofthe inowing air Vwill enter Y the `lowerend of the nozzle 25 by way of the openings 28. Thisvauxiliary air commingles with any unburned of the body portion, and an'outer ared hood surrounding the flared nozzle inl spaced substantially concentricrelav tion and engaging the radial elements and supported thereby, the top enddof the hood substantially ,contactingv Y "the top ofV they body portion and registering with `said 'opening in the top of thebody portion, the lower end?"l of the hood Yterminating nearV the'side openings of the ared nozzle, the hood being providednear its topgend 'with' atleast one Y .sideV opening registering `with passage of the radial element.

l '2. Af stove comprising a body portion upper end withupwardlyopening bayonet slots receiving the inner ends of the radial elements yfor detachably securing the nozzle to the spider support, the lower end ot said nozzle extending a substantial distance below the top ofthe body portion and into. the high temperature zone of the stove, spaced radial elementssecured tothe side wall of the nozzle, and an outer open-ended downwardly ared hood surrounding the nozzle in spaced gen- 'Wardly through passagesv 27kjand 3 2, the top of the collar 19 being .entirely openexcept for'the radial pins combustible products stillv Within the mainbombustion space and within the. nozzlel 25, andaids in igniting and inducing substantially complete'combustionV-of the same,

as'well as smoking offthe'stove to a minimum.'

` lIt vis to be Yunderstoodthat the 'form of ithe'inyention herewith shown and' described is'to be Ataken as a ,preferred example of the same, and that various changesfin the shape, size, and arrangement-of parts maybe resorted Y l:-t'o',`-witl:1out vdeparting :from the'spirit of the invention or Y scope of thesubjoinedclaims.

" Iclaim:

havingan opening, an upstanding collar -secured't'o said `top yadjacent said openings,V a :spider supportVV mounted' upon the top ofthe collarA over said opening and includingsubstantially horizontal radial elements having their inner ends extending radially inwardly of the margin of said opening,f`the spider support Ybeing-adapted for atthus reducing soot accumulation'in the stove 4and chimney i erally concentric relation therewith and resting upon said radial elements and supported entirely thereby, the top end of thehood substantially abutting theunderside ofthe top of said body portion Vandsubstantially registering with the opening inthe top of the body portion, the Vtop end of the hoed terminating short of the topend o f said nozzle and a substantial distancebelow Atheelevationoi the spider support, the lower end of the hood extending vnear the V elevation of the lower end of said nozzle. f

v '3.{Astove comprising a body portion including a top,

" an upstanding tubular Vextension secured to'said top of the body portion and communicating with .the interior of Vthe bodyV portion, a spider support resting upon Vthe top of the tubular extension and including aplurality of spaced substantially radial arms having their inner ends prio- 'jecting inwardlyof the side wall of thetubular extension,

anopen-ended downwardly ared nozzle disposed within the body ,portion and projecting a substantial distance below the toprof the body portion and having an upper end Vportioniextending Vthrough said-tubular extension in spaced Y substantially concentric relationV therewith, said upper end l Q1. A stove comprising a bodyportion -including a top 1 portion .of ythe unozzle having upwardly opening generally L-shaped slots formed therein to receive the inner V ends of saidV arms for detachably securng'thev nozzle tothe l spider supportfsaid arms bodily supporting the nozzle, f spaced radial elements 'securedto the Vnozzlebelowtlie top of the bodyportion, and an outer vopen-ended downwardly ared hood surrounding Vthe nozzle in spaced 'generallyV concentric relation thereto and restingVY upon and Y bodily supportedby Vsaid radial elements, the top end of said hood substantially registering with said tubular extension and abutting the top of the'body portion forproviding a substantially continuous annular'passage between the'nozzle, hood and tubular extension.

tachment with -a chimney extending aboyesaid opening,

adependingarednozzle arranged withinrthe body portionpand havingY its upper portion Y'extending into -said Vopening and provided near itsfupper 'end with Vslots receiving :the inner ,ends ofthe pins `for l-detachably `securingsthe nozzle to the spider,` support, the lower end of the Y nozzle'extendinga substantial distance below lthetop of the body portion `and into the high temperature'zone of Vthe stove, the nozzle having :a'plurality of side openings a formed therein nearY its lower'endfspaced'radial elements .Y Jsecured to thesideY walllof thefarednozzle, 'atleast one Y 'of therelements *having afpassage extending therethrough i 'and leading into'the'ared nozzle near'and below the top l 4. A Vstove comprising a body portion having atop,

an upstandingV tubular extension secured -to the topA and communicating with the interior of the body portion,

a spider support resting upon Vthe top of the tubular exten-Y sion-and including a plurality of spaced radial arms projecting inwardly of the side wall of the tubular extension, achimney adapter sleeve secured to the spidersupport and extending above said radial arms and tubularQXllSiQn for connection with the chimney, a downwardly hated V nozzle disposed within the body portion and ,havingan Y upper end p ortionextcnding ,throughthetubuhn extension in spaced substantially 'concentric relation thereto, the upper end portion of the nozzlehavingbayonetslots for cooperation with said arms so that the arms may support the weight of the nozzle, spaced radial projections formed upon said nozzle below the top of the body portion, and an outer downwardly flared hood surrounding Re- 1,506 Hefdefson June 30, 1863 the nozzle in spaced substantially concentric relation 5 1051587 Meissner IU15 19, thereto and resting upon said projections, the upper end 6931735 NOXOH F611 18y of the hood abutting the underside of the top of the body 727 459 SChOuP May 5, 1903 portion and substantially registering with the bore of said 7481472 Brandt et al DCC- 29, tubular extension v 1,441,531 CI'0S1611 Jan. 9, 10 2,153,106 Taylor Apr. 4, 2,319,131 Harrington May 11,

References Cited in the le of this patent UNITED STATES PATENTS 

